diff --git a/.github/workflows/downstream-ci-hpc.yml b/.github/workflows/downstream-ci-hpc.yml
index 6232d4b..d3b5c4a 100644
--- a/.github/workflows/downstream-ci-hpc.yml
+++ b/.github/workflows/downstream-ci-hpc.yml
@@ -455,7 +455,7 @@ jobs:
           ecmwf/ecflow:
             path: .github/ci-hpc-config.yml
             python: false
-            master_branch: master
+            master_branch: main
             develop_branch: develop
             input: ${{ steps.prepare-inputs.outputs.ecflow }}
             optional_matrix:
@@ -465,7 +465,7 @@ jobs:
           ecmwf/ecflow-light:
             path: .github/ci-hpc-config.yml
             python: false
-            master_branch: master
+            master_branch: main
             develop_branch: develop
             input: ${{ steps.prepare-inputs.outputs.ecflow-light }}
             optional_matrix: null
diff --git a/.github/workflows/downstream-ci.yml b/.github/workflows/downstream-ci.yml
index e0a6d27..5b91dea 100644
--- a/.github/workflows/downstream-ci.yml
+++ b/.github/workflows/downstream-ci.yml
@@ -473,7 +473,7 @@ jobs:
           ecmwf/ecflow:
             path: .github/ci-config.yml
             python: false
-            master_branch: master
+            master_branch: main
             develop_branch: develop
             input: ${{ steps.prepare-inputs.outputs.ecflow }}
             optional_matrix:
@@ -483,7 +483,7 @@ jobs:
           ecmwf/ecflow-light:
             path: .github/ci-config.yml
             python: false
-            master_branch: master
+            master_branch: main
             develop_branch: develop
             input: ${{ steps.prepare-inputs.outputs.ecflow-light }}
             optional_matrix: null
diff --git a/dependency_tree.yml b/dependency_tree.yml
index cd33b5f..dc94fa5 100644
--- a/dependency_tree.yml
+++ b/dependency_tree.yml
@@ -202,6 +202,7 @@ eccodes-python:
 
 ecflow:
   type: cmake
+  master_branch: main
   deps:
     - ecbuild
   optional_matrix:
@@ -215,6 +216,7 @@ ecflow:
 
 ecflow-light:
   type: cmake
+  master_branch: main
   deps:
     - eckit